Exercise: How Much Is Enough? (cont.)

"There is no question that short amounts of exercise can help you get fit, help you stay fit, and help you maintain your health," says personal fitness coach Susie Shina, author ofSixty Second Circuits. "You can stay fit in increments as short as 4 and 5 minutes at a time."

The best part about that is that everyone can find 5 minutes a few times a day, says Shina, owner of a mobile personal training center called Fitness 180.

"Some of these exercises can fit into a 5-minute time period at work, at your desk, waiting on line in the grocery store, even driving in your car," says Shina. "It's not an overwhelming task, and the benefits can be enormous."

Strength and conditioning coach Jim Massaro agrees.

"This is the way I personally work out -- and it's how I train others," says Massaro, founder of the Advanced Personal Training Center in Nyack, N.Y. "It works for beginners and, by increasing the intensity of what you do in those short increments, it can also work for advanced fitness training."

That said, some fitness experts warn that short workouts can have a downside.

"The bad part about short workouts is that they send the message that you can skimp on your health -- that less is more, that you don't have to invest in yourself to be healthy -- and that's the wrong message," says Mike Ryan, a personal trainer and member of the Gold's Gym Fitness Board.

While Ryan says brief bouts of exercise are a good way to get into the fitness mindset, he believes the eventual goal should be to do longer workouts. "Whatever you think you can accomplish with short workouts, you can accomplish that much more with longer workouts," he says.

Exercise: How Much Is the Bare Minimum?

While incorporating more exercise into our lives is a worthwhile goal, for many of us, just getting up off the couch is a big step toward better health.

So how much exercise do you really need? Most of the studies show that 5 minutes of continuous movement repeated during the day is about the bare minimum to have any effect, and fitness experts believe 10 minutes is more realistic.

"If 3 minutes is all you can do, if 2 minutes is all you can do, it's all better than nothing -- but you should be working up to a goal of at least 5 continuous minutes, and 10 is even better," says Shina.

It's important to make the most of those few minutes, she says. "You should come away from your 2 minutes or your 5 minutes or your 10 minutes of exercise feeling as if you have accomplished something," she says. "There is a certain amount of pushing your body that has to take place, even if it's just for 5 minutes."

And how often do you need to do these 5- to 10-minute bursts of activity?

According to the American College of Cardiology and the American College of Sports Medicine, good health really comes with 30 minutes of activity, at least 3-5 times a week. If you do the math, that means you'll need to fit in six daily sessions of 5 minutes apiece, or three daily bouts of 10 minutes apiece.